package com.aidong.util;

import java.io.*;
import java.security.MessageDigest;

import org.apache.commons.lang3.StringUtils;

public class StringUtil {
    public static String str;
    public static final String EMPTY_STRING = "";

    private final static String[] hexDigits = {"0", "1", "2", "3", "4", "5",
            "6", "7", "8", "9", "A", "B", "C", "D", "E", "F"};

    private static String byteToHexString(byte b) {
        int n = b;
        if (n < 0)
            n = 256 + n;
        int d1 = n / 16;
        int d2 = n % 16;
        return hexDigits[d1] + hexDigits[d2];
    }

    /**
     * 转换字节数组为16进制字串
     *
     * @param b 字节数组
     * @return 16进制字串
     */
    public static String byteArrayToHexString(byte[] b) {
        StringBuffer resultSb = new StringBuffer();
        for (int i = 0; i < b.length; i++) {
            resultSb.append(byteToHexString(b[i]));
        }
        return resultSb.toString();
    }

    public static String MD5Encode(String origin) {
        String resultString = null;
        try {
            resultString = new String(origin);
            MessageDigest md = MessageDigest.getInstance("MD5");
            resultString = byteArrayToHexString(md.digest(resultString
                    .getBytes()));
        } catch (Exception ex) {
        }
        return resultString;
    }

    public static boolean isEmpty(String value) {
        return StringUtils.isEmpty(value);
    }

    public static String convertStr(Object value) {
        if (value == null) {
            return null;
        }

        if (value instanceof String) {
            return (String) value;
        }

        return String.valueOf(value);
    }

    public static int convertInt(Object value) {
        if (value == null) {
            return 0;
        }

        String str = convertStr(value);
        if (StringUtil.isEmpty(str)) {
            return 0;
        }
        return Integer.valueOf(str);
    }
}
